WO2023281744A1

WO2023281744A1 - Optical node, rotation angle deviation compensation system, and rotation angle deviation compensation method

Info

Publication number: WO2023281744A1
Application number: PCT/JP2021/025991
Authority: WO
Inventors: 友裕川野; 和典片山; 和英中江; ひろし渡邉; 達也藤本
Original assignee: 日本電信電話株式会社
Priority date: 2021-07-09
Filing date: 2021-07-09
Publication date: 2023-01-12
Also published as: JPWO2023281744A1

Abstract

This optical node comprises: an input-side optical port (S1-8) to which optical testing light is inputted; a first optical switch (S2-14(a)) that is connected to the input-side optical port and has a plurality of channels; a first rotation mechanism for rotating the first optical switch; a second optical switch (S2-14(b)) that is connected to the first optical switch and has a plurality of channels; a second rotation mechanism for rotating the second optical switch; an output-side port (S1-90) connected to the second optical switch and from which the optical test light is outputted; an optical port monitoring unit (S2-20) for measuring the light intensity of the optical testing light that passes through the output-side port; and an optical node control unit (S2-9) connected to the first rotation mechanism, the second rotation mechanism, and the optical port monitoring unit, the optical node control unit (S2-9) performing rotation angle deviation compensation in which, for each of a designated channel of the first optical switch and a designated channel of the second optical switch, the optical switches are caused to rotate by a minute angle and then the optical port monitoring unit is caused to measure the light intensity, the rotation angle of each optical switch at which the light intensity of the optical testing light is at maximum is extracted, and a database indicating the rotation angle for each designated channel is updated.

Description

Optical node, rotation angle deviation compensation system and rotation angle deviation compensation method

The present invention mainly relates to an optical node that has the function of driving optical switches and sensors with optical power supply in an optical fiber network.

In a fiber network, an optical node as shown in Non-Patent Document 1, for example, has been proposed as an optical node that remotely drives an optical switch by optical power supply. According to Non-Patent Document 1, in an optical node that operates by optical power feeding, an N×N switch is realized by arranging 2N 1×N switches in multiple stages.

In addition, as an all-optical switch that switches paths of light as it is, an optical switch as shown in Non-Patent Document 2, for example, has been proposed. According to Non-Patent Document 2, an optical fiber type mechanical optical switch that controls the butting of optical fibers or optical connectors by a motor or the like is inferior to other methods in terms of slow switching speed, but has low loss and low wavelength dependence. It has many advantages over other methods in terms of flexibility, multi-port capability, and the provision of a self-holding function that maintains the switching state when the power is lost.

However, in the related technology described in Non-Patent Document 1, there is no means for confirming whether the optical switch is connected with the minimum connection loss, so there is a risk of excessive loss occurring in the optical node. Also, in Non-Patent Document 2, when the optical fiber connection is switched by the rotation of the motor, etc., the positions of the optical fiber cores facing each other in the optical switch are displaced due to disturbance such as rotational slip and vibration of the motor. In this case, there is a problem that there is no means for returning the optical fiber core position.

In order to solve the above-mentioned problems, the present invention provides an optical node capable of compensating the rotation angle deviation of the optical fiber core of the ferrule rotary optical switch and reducing the connection loss caused in the optical switch, and the rotation angle deviation. It is an object of the present invention to provide a compensation system and method for compensating rotational angular misalignment.

In order to achieve the above object, the optical node, the rotation angle deviation compensation system, and the rotation angle deviation compensation method of the present disclosure input test light to a target port, switch an optical switch to a designated channel, and rotate the optical switch by a small angle. and the rotation angle at which the measured light intensity is maximized is stored as the set angle for the designated channel.

Specifically, the optical node according to the present disclosure includes:
an input-side optical port into which the optical test light is input;
a first optical switch connected to the input side optical port and having a plurality of channels;
a first rotating mechanism for rotating the first optical switch;
a second optical switch connected to the first optical switch and having a plurality of channels;
a second rotating mechanism for rotating the second optical switch;
an output side port connected to the second optical switch and outputting the optical test light;
an optical port monitoring unit that measures the optical intensity of the optical test light passing through the output port;
connected to the first rotating mechanism, the second rotating mechanism, and the optical port monitoring unit, and rotating the optical switch at a small angle for the designated channel of the first optical switch and the designated channel of the second optical switch, respectively; After rotating, the optical port monitoring unit measures the light intensity, extracts the rotation angle of the optical switch at which the light intensity of the optical test light reaches the maximum value, and creates a database representing the rotation angle of each designated channel. an optical node control unit that compensates for rotational angle deviation to be updated;
Prepare.

For example, an optical node according to the present disclosure:
The first optical switch and the second optical switch are
an input-side ferrule in which the centers of one or more optical fiber cores are arranged on the circumference of a circle centered at the center in a cross section perpendicular to the longitudinal direction;
and an output ferrule in which the centers of one or more optical fiber cores are arranged on the circumference of the circle whose center is the center in the cross section perpendicular to the longitudinal direction, and butt together with the central axes in the longitudinal direction aligned. and
At least one of the input side ferrule and the output side ferrule can be rotated to switch between a plurality of channels and can be rotated by a minute angle.

For example, an optical node according to the present disclosure:
an input/output unit into which downstream light is input;
a power supply unit that accumulates the downstream light input to the input/output unit as electric power,
The first rotating mechanism, the second rotating mechanism, the optical port monitoring unit, and the optical node control unit operate with electric power accumulated in the power supply unit.

For example, in the optical node according to the present disclosure,
The optical node controller performs the rotation angle deviation compensation when it detects vibration by itself or when it receives a notification from the outside.

For example, in the optical node according to the present disclosure,
The optical node controller performs the rotation angle deviation compensation each time the optical path is switched by the first optical switch or the second optical switch, or each time the optical path is switched a certain number of times.

Specifically, the rotation angle deviation compensation system according to the present disclosure includes:
the optical node; and a control device that supplies the downstream light to the power feeding portion of the optical node and inputs the optical test light.

Specifically, the rotation angle deviation compensation system according to the present disclosure includes:
The optical node is connected to an external network or has a sensor that detects vibration, and when the occurrence of a disaster is detected by the external network or when the sensor detects vibration, the occurrence of the disaster or the vibration is detected. to the optical node as the notification.

Specifically, the rotation angle deviation compensation method according to the present disclosure includes:
inputting the optical test light into the input side port;
switching a first optical switch connected to the input port to a designated channel;
switching a second optical switch connected to the designated channel of the first optical switch to the designated channel;
measuring the optical intensity of the optical test light output to the output side port connected to the designated channel of the second optical switch;
For each of the designated channel of the first optical switch and the designated channel of the second optical switch, the optical switch is rotated by a small angle to measure the optical intensity, and the optical test light has the maximum optical intensity. The rotation angle of the switch is extracted and a database representing said rotation angle for each designated channel is updated.

The optical node, the rotation angle deviation compensation system, and the rotation angle deviation compensation method of the present disclosure input test light to the target port, switch the optical switch to the designated channel, rotate the optical switch by a small angle, and measure the light intensity is stored as the set angle for the designated channel. Accordingly, an optical node, a rotation angle deviation compensation system, and a rotation angle deviation compensation method are provided, which can compensate for the rotation angle deviation of the optical fiber core of the ferrule rotary optical switch and reduce the connection loss that occurs in the optical switch. can provide.

The above inventions can be combined as much as possible.

INDUSTRIAL APPLICABILITY According to the present disclosure, an optical node, a rotation angle deviation compensation system, and a rotation angle deviation that can compensate for the rotation angle deviation of the optical fiber core of the ferrule rotary optical switch and reduce the connection loss that occurs in the optical switch Compensation methods can be provided.

1 is an example of a configuration diagram of an optical node system of the present disclosure; FIG. 1 is an example of a configuration diagram of an optical node of the present disclosure; FIG. 1 is an example of a configuration diagram of an optical switch of the present disclosure; FIG. FIG. 2 is an example of a flow chart showing a method for compensating for rotational angle deviation of an optical switch according to the present disclosure; It is an example of the figure which shows an example of the light intensity measurement result in the rotation angle deviation compensation method of an optical switch. It is an example of the figure which shows an example of the light intensity measurement result in the rotation angle deviation compensation method of an optical switch. FIG. 10 is an example of a diagram showing an example of updating a database when a minute angular deviation occurs in a method for compensating for rotational angular deviation of an optical switch;

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In addition, this invention is not limited to embodiment shown below. These implementation examples are merely illustrative, and the present disclosure can be implemented in various modified and improved forms based on the knowledge of those skilled in the art. In addition, in this specification and the drawings, constituent elements having the same reference numerals are the same as each other.

(Embodiment 1)
FIG. 1 shows an example of the configuration of an optical node system according to an embodiment of the present invention. The controller S1-1 shown in FIG. 1 is installed in an environment capable of supplying power, and includes a light source S1-2, an optical circulator S1-3, an optical receiver S1-4, a controller S1-5, and an optical test light source S1-. 20, an optical selector S1-21, an optical test light input coupler S1-22, an external network S1-30 for acquiring disaster information, and a vibration detection sensor S1-31. A laser beam emitted from the light source S1-2 is input to the transmission line optical fiber S1-6 via the optical circulator S1-3. For example, the wavelength of laser light can be exemplified from 1480 nm to 1490 nm. Also, the power of the laser light output from the light source S1-2 may be about +10 to 17 dBm. The laser light is used to optically power the optical node S1-7.

The optical node S1-7 is installed at an arbitrary location, such as a location without a power supply, and is connected to the control device S1-1 via the transmission line optical fiber S1-6. The optical node S1-7 has a plurality of transmission line optical fibers other than the transmission line optical fiber (hereinafter referred to as input/output optical fibers S1-8 and S1-9 to distinguish from the transmission line optical fiber S1-6). It is connected.

The optical selector S1-21 has a plurality of ports and is connected to the optical node S1-7 via the optical test light input coupler S1-22 and the input/output optical fiber S1-8. The optical selector S1-21 is connected to the optical test light source S1-20, and transmits an optical test light S2-200 (to be described later) from the optical test light source S1-20 from an arbitrary port of the optical selector S1-21 to an optical test light input coupler. It is input to the optical node S1-7 via S1-22 and input/output optical fiber S1-8.

The external network S1-30 for obtaining disaster information and the vibration detection sensor S1-31 are connected to the controller S1-5. It is used to quickly detect the impact and compensate for rotational angle deviation in the event of an accident involving a The vibration detection sensor S1-31 may be, for example, a one-axis or two-axis acceleration sensor.

The controller S1-5 may have a function of analyzing an upstream frame included in the upstream light S1-11 from the optical node S1-7 received by the optical receiver S1-4. The upstream frame may include an input instruction for the optical test light S2-200, which will be described later.

In addition, the controller S1-5 detects the occurrence of a disaster such as an earthquake, which has a high risk of causing a deviation in the rotation angle of the optical switch, or an accident involving impact, by means of the external network S1-30 and the vibration detection sensor S1-31. In some cases, the light source S1-2 may be caused to output a downward light S1-10 including an instruction to detect the occurrence of a disaster or vibration, or to perform rotation angle deviation compensation, which will be described later.

Further, the controller S1-5 causes the optical test light source S1-20 to input the optical test light S2-200, which will be described later, from the port selected by the optical selector S1-21 to the optical node S1-7 in the rotational angle deviation compensation. and the optical selector S1-21. The controller S1-5 may then notify the optical node S1-7 of the port for inputting the optical test light S2-200 using the downstream light S1-10.

An example of the internal configuration of the optical node S1-7 is shown in FIG.
The optical node S1-7 according to this embodiment is
an input-side optical port (S1-80) into which optical test light is input;
a first optical switch (S2-14(a)) connected to the input side optical port and having a plurality of channels;
a first rotating mechanism (S3-1) for rotating the first optical switch;
a second optical switch (S2-14(b)) connected to the first optical switch and having a plurality of channels;
a second rotating mechanism (S3-1) for rotating the second optical switch;
an output side port (S1-90) connected to the second optical switch and outputting the optical test light;
an optical port monitoring unit (S2-20) for measuring the optical intensity of the optical test light passing through the output port;
connected to the first rotating mechanism, the second rotating mechanism, and the optical port monitoring unit, and rotating the optical switch at a small angle for the designated channel of the first optical switch and the designated channel of the second optical switch, respectively; After rotating, the optical port monitoring unit measures the light intensity, extracts the rotation angle of the optical switch at which the light intensity of the optical test light reaches the maximum value, and creates a database representing the rotation angle of each designated channel. an optical node control unit (S2-9) that performs rotation angle deviation compensation to be updated;
Prepare.

The optical node S1-7 shown in FIG. 2 receives the downstream light S1-10 including the modulated period and the non-modulated period, and functions as an input/output unit for outputting the upstream light S1-11 containing information. -1 and
an input gate optical switch S2-2 that transmits the downstream light S1-10 input to the optical branching unit S2-1 for an arbitrary period and supplies the downstream light S1-10 to the power supply unit S2-22;
an optical receiver S2-7 for constantly receiving the downstream light S1-10 input to the optical splitter S2-1;
Of the downstream light S1-10 input to the optical branching unit S2-1, the downstream light S1-10 in the non-modulation period is reflected and non-reflected based on information to generate the upstream light S1-11. an optical switch S2-8;
may be provided.

In addition, since the optical node S1-7 has the function of optical line switching, the optical node S1-7 operates with the electric power accumulated in the power supply section S2-22, and optical path switching for arbitrarily switching a plurality of optical paths. A section S2-30 may be further provided, and the information may be the state of the optical path and the input indication of the optical test light.
The optical path switching unit S2-30
a plurality of optical ports (S1-80, S1-90) to which a plurality of communication optical fibers (S1-8, S1-9) are respectively connected;
Operates on power stored in the power supply unit S2-22, and outputs optical signals input to optical ports (S1-80, S1-90) to arbitrary optical ports (S1-80, S1-90). an optical path changeover switch (cross connect section S2-16) that switches the optical path;
an optical port monitoring unit S2-20 that monitors the optical signals passing through the optical ports (S1-80, S1-90) and monitors the state of the optical path;
further provide.

The optical node S1-7 shown in FIG. 2 sends the downstream light S1-10 from the transmission line optical fiber S1-6 to the optical branching section S2-1, the input gate optical switch S2-2, the photoelectric conversion element S2-3, and the photoelectric conversion element S2-3. It is characterized by supplying drive power S2-5 for all the active elements contained in the optical node S1-7 via the secondary battery S2-4. Incidentally, the photoelectric conversion element S2-3 and the secondary battery S2-4 are the "power feeding section S2-22", and the input gate optical switch S2-2, the reflection switch S2-8, the cross-connect section S2-16, the optical The port monitor S2-20 and the optical node controller S2-9 are included in the active elements.

The optical splitter S2-1 is a split ratio coupler, and guides the optical power to the input gate optical switch S2-2.

The input gate optical switch S2-2 plays the role of a gate switch that can select whether or not to transmit the downstream light S1-10 that has passed through the optical splitter S2-1 to another path. A plurality of optical nodes S1-7 can be controlled by connecting the optical nodes S1-7. Further, the input gate optical switch S2-2 serves as a gate switch that can select whether or not to transmit the downstream light S1-10 that has passed through the optical splitter S2-1 to the photoelectric conversion element S2-3. It may be used to prevent overcharging of the secondary battery S2-4. Since the input gate optical switch S2-2 operates frequently, it is desirable to operate at a low voltage and with very low power consumption of several nW or less. For example, as the input gate optical switch S2-2, it is possible to use an electrostatically driven MEMS optical switch that requires less driving power and is generally available.

For the photoelectric conversion element S2-3, one capable of receiving the wavelength of the laser light emitted from the light source S1-2 is used. As the photoelectric conversion element S2-3, an easily available element suitable for the long wavelength band of 1300 nm to 1600 nm for communication, such as an element composed of indium gallium arsenide, an open circuit voltage of 5 V or less, and a conversion efficiency of about 30% is used. can. For example, the photoelectric conversion element S2-3 is an optical feeding converter (https://www.kyosemi.co.jp/resources/ja/products/sensor/nir_photodiode/kpc8_t/kpc8_t_spec.pdf). Also, if the power of the laser light transmitted through the transmission path optical fiber S1-6 is, for example, about 2 mW, it can be used for optical power supply. Note that the power varies depending on the device used for optical power supply.

The secondary battery S2-4 is used to store electric power energy converted by the photoelectric conversion element S2-3, and for example, an electric double layer capacitor or the like is used. In addition, in voltage supply to each active element, it is assumed that the voltage boosted by a DC/DC converter or the like can be appropriately adjusted.

The other side of the optical branching section S2-1 is guided to another optical branching section S2-6 and inputted to the optical receiver S2-7 and the reflection optical switch S2-8. The optical receiver S2-7 is arranged to always receive the downstream light S1-10 regardless of the path state of the input gate optical switch S2-2, and accepts control signals from the controller S1-1.

The reflected light switch S2-8 is an optical switch capable of ON/OFF control of whether or not part of the downward light S1-10 is totally reflected. The reflected light switch S2-8 utilizes the downstream light S1-10 to modulate upstream light toward the control device S1-1. It is desirable that the reflective optical switch S2-8 operates at a low voltage and with very small power consumption of several nW or less. For example, as the reflective optical switch S2-8, an electrostatically driven MEMS optical switch that requires less driving power and is generally available can be used.

In the example of FIG. 2, the optical cross connect section S2-16 comprises a plurality of optical switches S2-14. The optical cross-connect unit S2-16 arranges a plurality of optical switches S2-14(a) having 1 input and N outputs on the optical port S1-80 side, and a plurality of optical switches S2-14(a) having N inputs and 1 output on the optical port S1-90 side. optical switches S2-14(b) are arranged, and the optical waveguide wiring S2-15 is cross-wired between them. The optical cross-connect unit S2-16 constitutes an N×N port optical cross-connect. The wiring of the optical waveguide wiring S2-15 is free depending on the application. Wiring is also possible. Also, the number of input/output ports of the optical cross-connect section S2-16 does not have to be symmetrical, and an asymmetric configuration such as M.times.N can also be implemented. Thus, the optical cross-connect section S2-16 is characterized by being composed of a plurality of optical switches S2-14 as in this embodiment.

However, the standby power consumption of the optical cross-connect unit S2-16 greatly affects the power management of the entire system. For this reason, the optical switch S2-14 is preferably a self-holding optical switch that does not require power during standby and that maintains the switching state even when power is lost.

The reason why the optical cross-connect section S2-16 has a configuration in which a plurality of optical switches S2-14 are arranged on both sides of the optical ports (S1-80, S1-90) is as follows. Normally, a self-holding optical switch having a plurality of output ports has a phenomenon in which light is output to an unintended port during a switching operation, which may lead to a communication accident. Providing a plurality of optical switches on both the input side and the output side requires switching of at least two optical switches to switch one optical path. Even if one optical switch outputs light to an unintended port, the light can be blocked by the other optical switch, thereby preventing communication accidents caused by unintended light output.

The optical line switching unit S2-30 also has an optical port monitoring unit S2-20 that monitors the connection information of the optical cross connect S2-16. The optical port monitoring section S2-20 is arranged on the optical port S1-80 side and the optical port S1-90 side of the optical cross-connect section S2-16, and monitors communication light or test light input from the input/output optical fiber S1-8. The ports of the plurality of optical switches S2-14 in the optical cross connect section S2-16 are monitored by optically branching and receiving the communication light or test light output from the input/output optical fiber S1-9. As means for optically branching the communication light or test light by the optical port monitor S2-20, there is, for example, a commonly available 99:1 optical coupler. An optical receiver for reading optically branched light includes, for example, a photodiode that is generally available.

For each optical switch S2-14, the optical port monitoring unit S2-20 monitors an optical fiber connected to each channel on the input side of the optical switch S2-14 and each channel on the output side of the optical switch S2-14, for example, the input side optical fiber S2 described later. -100 and output optical fiber S2-101, a portion of the optical signal may be sampled and the optical intensity measured.

The optical port monitoring unit S2-20 confirms the optical port to be switched before switching the optical cross-connect unit S2-16, and checks whether the optical port has been correctly switched after switching the optical cross-connect unit S2-16. can be identified and these can be referred to as "lightpath states". In addition, by monitoring the optical loss with the optical port monitoring unit S2-20 of the plurality of optical nodes S1-7, it is possible to prevent disconnection of the optical transmission line composed of the input/output optical fibers (S1-8 and S1-9). When an error occurs, it is possible to identify between which nodes the error occurred. In this way, the location where an abnormality detected by the optical port monitoring units S2-20 of the plurality of optical nodes S1-7 has occurred can also be set as the "state of the optical path".

The optical node S1-7 has an optical node controller S2-9 for control. The optical node controller S2-9
A power control function that monitors the amount of electricity stored in the power supply unit S2-22;
a downstream frame analysis function for analyzing a modulated signal included in the downstream light in the modulation period;
a switching operation control function for instructing switching of the input gate optical switch S2-2 based on the amount of charge and instructing switching of the optical path switching unit S2-30 based on the analysis result of the modulated signal;
an optical port monitoring function that uses the "state of the optical path" as the information;
an upstream signal generating function for driving the reflected light switch S2-8 based on the information;
may have
These five functions (1) to (5) will be explained.

(1) Downlink Frame Analysis Function The downlink frame analysis function is a function to analyze the downlink frame included in the downlink light S1-10 from the control device S1-1 received by the optical receiver S2-7. The light source S1-2 of the controller S1-1 modulates the intensity of the output laser light based on the signal from the controller S1-5, and converts it into an informationized downstream frame such as TTL (Time to live) or CMOS signal. do. The frame includes a request for node information, an execution instruction for switching switches (input gate optical switch S2-2 and optical switch S2-14), and the like. The downstream frame may include a notification of the occurrence of a disaster detected by the external network S1-30 or the vibration detection sensor S1-31, a notification of the detection of vibration, or an instruction to perform rotation angle deviation compensation, which will be described later.

(2) Uplink signal generation function The uplink signal generation function works in conjunction with the downlink frame analysis function, uses the "state of the optical path" and the input instruction of the optical test light as the information, modulates the reflected optical switch S2-8, and performs the uplink signal. This is the function of generating the signal light S1-11.

(3) Switching Operation Control Function The switching operation control function works in conjunction with the downstream frame analysis function to perform the input gate optical switch S2-2 to be switched or any optical switch S2 provided in the optical cross-connect section S2-16. -14 is specified to command switching to an arbitrary port. As a specific circuit configuration for realizing the switching operation control function, a drive circuit attached to each optical switch can be arbitrarily controlled by bus communication (for example, I2C, etc.) using the optical node controller S2-9 as a master. can be exemplified by a circuit that sends an instruction to a drive circuit having an address of and controls the switching operation of an arbitrary optical switch S2-14.

(4) Power Monitoring Function The power monitoring function is a function for monitoring the amount of energy stored in the secondary battery S2-4. The optical node control unit S2-9 constantly grasps the amount of stored energy in the secondary battery S2-4 via a voltage monitor or the like, and based on the set threshold value, the control device S1-1 via the upstream signal generation function. to notify.

(5) Optical Port Monitoring Function The optical port monitoring function is a function of monitoring the optical port information of the optical port monitoring section S2-20. When receiving an inquiry from the control device S1-1, the optical node control unit S2-9 grasps the optical port information via the voltage monitor of the optical receiver provided in the optical port monitoring unit S2-20. , to the controller S1-1 via the upstream signal generation function.

As described above, the optical node control unit S2-9 allows the optical node S1-7 itself to manage the amount of stored energy and to perform upstream communication with the control device S1-1 by linking the above five functions. and downlink communication for receiving an execution instruction from the control device S1-1.

An example of the structure of the 1×N optical switch S2-14 that constitutes the optical cross connect S2-16 will be described with reference to FIG. As a structure of the 1×N optical switch S2-14, as shown in FIG. The installed output side ferrule S3-3 is positioned by the sleeve S3-4 and butted against each other.

For example, the output-side ferrule S3-3 may have a structure in which the centers of the N output-side optical fibers S2-101 are on the same circumference around the center of the output-side ferrule S3-3 in the cross section of the ferrule. . For example, the input ferrule S3-2, in the cross section of the input ferrule, has the same circumference as the output side optical fiber S2-101 of the output ferrule S3-3 with the center of the input ferrule S3-2 as the center. A structure in which the center of the input side optical fiber S2-100 is located on the circumference may be used. In addition, the sleeve S3-4 positions the input ferrule S3-2 and the output ferrule S3-3 such that the longitudinal central axes of the input ferrule S3-2 and the output ferrule S3-3 are aligned. You may Note that the input side optical fiber S2-100 is an optical fiber into which the optical test light S2-200 described later is incident among the input/output optical fibers S1-8.

The sleeve S3-4 is fixed by a fixing jig S3-7. A flange is attached to each ferrule (S3-2, S3-3) (S3-5, S3-6). For example, in the optical cross connect S2-16, as shown in FIG. 3, the input side ferrule S3-2 is rotated by attaching a ferrule rotating actuator S3-1 as a rotating mechanism to the input side flange S3-5 of the optical switch S2-14. Rotate to achieve switching. The ferrule rotating actuator S3-1 is supplied with drive power S2-5 from the optical node S1-7, and receives a rotation control signal from the optical node controller S2-9, and can rotate at an arbitrary rotation angle. It becomes possible. The optical switch S2-14(a) shown in FIG. 2 may have a structure similar to the structure of the 1×N optical switch S2-14 in FIG. 3, and the optical switch S2-14(b) shown in FIG. may have an N×1 optical switch structure obtained by horizontally reversing the structure of the 1×N optical switch S2-14 in FIG. The N×1 optical switch, which is the optical switch S2-14(b), may be provided with a ferrule rotating actuator S3-1 as a rotating mechanism in the same manner as the 1×N optical switch.

In addition, the optical node S1-7 is also provided with a vibration detection sensor S2-31 connected to the optical node control unit S2-9 so that vibration caused by disturbance can be detected.

Next, when the optical switch S2-14 is switched, the rotation angle deviation of the optical fiber core of the optical switch S2-14 occurs due to the disturbance such as the slip or impact of the ferrule rotation actuator S3-1 itself. A rotation angle deviation compensation method will be described with reference to FIG. Note that the optical node controller S2-9 may perform rotation angle deviation compensation each time the optical path is switched by the optical switch S2-14.

First, the target port is selected by the optical selector S1-21, and the optical test light S2-200 is input through the optical test light input coupler S1-22 (step S01). Next, the optical switch S2-14(a) on the input side (previous stage) is switched to the designated channel (step S02). After that, the optical switch S2-14(b) on the output side (latter stage) is switched to the designated channel (step S03).

The optical port monitoring unit S2-20 measures the optical intensity of the optical test light S2-200 output from the designated channel of the optical switch S2-14(b) (step S04). Next, the front-stage optical switch S2-14(a) is rotated by a minute angle, eg, 1 degree, in the positive and negative directions (step S05). After the optical switch S2-14(a) rotates, the optical intensity of the optical test light S2-200 output from the designated channel of the optical switch S2-14(b) is measured (step S06), and the maximum optical intensity (step S07). In step S07, for example, as shown in FIG. 5, when measuring at three angles (-1deg, 0deg, 1deg), when the peak value is obtained at the middle angle (0deg) among the three angles , the process proceeds to the next process step S08. The maximum value may be the peak value when the peak value is obtained at the middle angle of the three angles.

If the maximum value is not obtained at three angles (-1deg, 0deg, 1deg) as in FIG. 6, that is, the middle angle (0deg) among the three angles (-1deg, 0deg, 1deg) If the peak value is not obtained in step S05, the rotation is further performed by a minute angle so as to obtain the maximum value, and the maximum value is obtained. In FIG. 6, since the maximum value could not be obtained at the rotation angles of -1 deg, 0 deg, and 1 deg, the light intensity measurement described above was further performed with the rotation angle of 2 deg, and the results are shown. In FIG. 6, attention is paid to the light intensity of 0 deg, 1 deg, and 2 deg, and since the peak value is obtained at 1 deg, which is the middle angle, it can be judged that the maximum value has been obtained.

FIG. 7 shows a database representing each channel and the rotation angle corresponding to the channel for the optical switch S14-2 having 10 channels. If the maximum value of light intensity can be acquired, the database is updated as shown in FIG. 7 (step S08). Note that the database may be updated only when the rotation angle for which the maximum value was acquired is different from the preset rotation angle. FIG. 7 shows an example of updating the database for

channels

1, 5 and 8, but is not limited to this. By updating the database, the data can be used next time.

After compensating for the rotational angle deviation of the front-stage optical switch S2-14(a), the rear-stage optical switch S2-14(b) is similarly rotated by a minute angle (step S09). After the optical switch S2-14(b) rotates, the optical intensity of the optical test light S2-200 output from the designated channel of the optical switch S2-14(b) is similarly measured (step S10). Steps S09 and S10 are performed until the maximum value of the optical test light S2-200 is obtained (step S11). If the maximum value of the light intensity can be acquired, the database is updated (step S12), and the process of the rotation angle deviation compensation method is completed.

The optical node controller S2-9 provided in the optical node S1-7 of the present invention can also be realized by a computer and a program, and the program can be recorded on a recording medium or provided through a network.

(Embodiment 2)
The optical node, rotational angle deviation compensation method, and rotational angle deviation compensation system according to the present embodiment will be described below. The present embodiment differs from the first embodiment only in the timing of performing rotation angle deviation compensation.

As described in the first embodiment, if rotational angle deviation compensation is performed at each timing of optical path switching by the optical switch S2-14, the optimum optical connection state can be realized for each switching, but the frequency of use is reduced accordingly. can be high and consume extra power (sequential compensation mode).

Therefore, as an example of operation, it is possible to reduce power consumption more than in the sequential compensation mode (regular compensation mode) by compensating for rotational angle deviation at each constant number of switching times of the optical switch S2-14.

Also, if a strong impact occurs to the optical node S1-7 due to a natural disaster such as an earthquake or an accident instead of the timing of optical switching, it is necessary to detect this immediately and compensate for the rotation angle deviation (emergency compensation mode). The detection of impact may be performed, for example, by the vibration detection sensor S2-31 provided in the optical node S1-7, or may be performed by the vibration detection sensor S1-31 provided in the control device S1-1. . Alternatively, the impact detection may be performed by the control device S1-1 connecting to the external network S1-30 and acquiring information.

(Effect of the present invention)
As described in the above two embodiments, by using the optical node, the rotation angle deviation compensation system, and the rotation angle deviation compensation method of the present invention, the risk of increasing the loss of the optical connection of the optical switch can be greatly reduced. , it becomes possible to provide a highly reliable optical fiber network system.

The above inventions can be combined as much as possible.

The optical node, rotational angle deviation compensation system, and rotational angle deviation compensation method according to the present disclosure can be applied to the information and communication industry.

S1-1: control device S1-2: light source S1-3: optical circulator S1-4: optical receiver S1-5: controller S1-6: transmission line optical fiber S1-7: optical node S1-8: input/output light Fiber S1-9: input/output optical fiber S1-10: downstream light S1-11: upstream light S1-20: optical test light source S1-21: optical selector S1-22: optical test light input coupler S1-30: external Network S1-31: Vibration detection sensor S1-80, S1-90: Optical port S2-1: Optical splitter S2-2: Input gate optical switch S2-3: Photoelectric conversion element S2-4: Secondary battery S2-5 : Drive power S2-6: Optical coupler S2-7: Optical receiver S2-8: Reflected optical switch S2-9: Optical node controller S2-14: Optical switch S2-15: Optical waveguide wiring S2-16: Light Cross-connecting section S2-20: Optical port monitoring section S2-22: Power feeding section S2-30: Optical path switching section S2-31: Vibration detection sensor S2-100: Input side optical fiber S2-101: Output side optical fiber S2- 200: Optical test light S3-1: Ferrule rotation actuator S3-2: Input side ferrule S3-3: Output side ferrule S3-4: Sleeve S3-5: Input side flange S3-6: Output side flange S3-7: fixing jig

Claims

an input-side optical port into which the optical test light is input;
a first optical switch connected to the input side optical port and having a plurality of channels;
a first rotating mechanism for rotating the first optical switch;
a second optical switch connected to the first optical switch and having a plurality of channels;
a second rotating mechanism for rotating the second optical switch;
an output side port connected to the second optical switch and outputting the optical test light;
an optical port monitoring unit that measures the optical intensity of the optical test light passing through the output port;
connected to the first rotating mechanism, the second rotating mechanism, and the optical port monitoring unit, and rotating the optical switch at a small angle for the designated channel of the first optical switch and the designated channel of the second optical switch, respectively; After rotating, the optical port monitoring unit measures the light intensity, extracts the rotation angle of the optical switch at which the light intensity of the optical test light reaches the maximum value, and creates a database representing the rotation angle of each designated channel. an optical node control unit that compensates for rotational angle deviation to be updated;
An optical node with
The first optical switch and the second optical switch are
an input-side ferrule in which the centers of one or more optical fiber cores are arranged on the circumference of a circle centered at the center in a cross section perpendicular to the longitudinal direction;
and an output ferrule in which the centers of one or more optical fiber cores are arranged on the circumference of the circle whose center is the center in the cross section perpendicular to the longitudinal direction, and butt together with the central axes in the longitudinal direction aligned. and
2. The optical node according to claim 1, wherein at least one of said input side ferrule and said output side ferrule is capable of switching a plurality of channels by rotating and rotating at a minute angle.
an input/output unit into which downstream light is input;
a power supply unit that accumulates the downstream light input to the input/output unit as electric power,
3. The apparatus according to claim 1, wherein said first rotating mechanism, said second rotating mechanism, said optical port monitoring unit, and said optical node control unit operate with electric power accumulated in said power supply unit. Optical node as described.
4. The optical node according to any one of claims 1 to 3, wherein the optical node controller performs the rotation angle deviation compensation when it detects vibration by itself or when it receives a notification from the outside. .
The optical node controller is characterized in that the rotational angle deviation compensation is performed each time the optical path is switched by the first optical switch or the second optical switch, or each time the optical path is switched a certain number of times. 4. An optical node according to any one of claims 1 to 3.
an optical node according to any one of claims 3 to 5; a control device that supplies the downstream light to the power supply unit of the optical node and inputs the optical test light;
A rotational angular misalignment compensation system comprising:
5. The optical node according to claim 4, and a sensor connected to an external network or detecting vibration, wherein the disaster occurs when the external network detects the occurrence of a disaster or when the sensor detects the vibration. a control device that transmits detection of the vibration to the optical node as the notification;
A rotational angular misalignment compensation system comprising:
inputting the optical test light into the input side port;
switching a first optical switch connected to the input port to a designated channel;
switching a second optical switch connected to the designated channel of the first optical switch to the designated channel;
measuring the optical intensity of the optical test light output to the output side port connected to the designated channel of the second optical switch;
For each of the designated channel of the first optical switch and the designated channel of the second optical switch, the optical switch is rotated by a small angle to measure the optical intensity, and the optical test light has the maximum optical intensity. A rotation angle deviation compensation method for extracting a rotation angle of a switch and updating a database representing said rotation angle for each designated channel.